The present invention is directed to a vertically-movable roof for a pilot house or helm station of a boat in order to vary the height of the roof, so that during inclement weather, the roof may be lowered and the control-compartment closed, or may be elevated during sunny or warm weather where the compartment is open to the ambient surrounding. Helm stations for relatively large boats, as yachts, is the compartment where controls for the boat are located, are generally and conventionally provided with an elevated roof raised above the remainder of the control compartment, thus providing an open space between the interior of the compartment and the outside. Typically, when one desires to close off such opening to the outside, a canvas or other type of enclosure is wrapped about the open space between the bottom of the elevated roof and the upper surfaces of the compartment side walls and front wall or wind shield, or the like. Such enclosure may be snapped into place, or otherwise removably secured. Smaller boats of the 11-30 feet range generally have a center console or pilot house without any general protective covering at all, as in a helm station. The present invention is as equally applicable to a pilot house a sit is to helm station, so as to define a new type of center control compartment for a smaller boat with the advantages of the helm station of a larger boat. Helm stations of large boats typically include a rear upstanding radar arch, which sometimes actually mounts radar, but usually is only an aesthetic appurtenance having remained even though its prior function as radar-equipment support has been made largely obsolete. Some of the helm stations above-referred to do utilize the upper surface of the radar arch to support a fixed roof at the rear, or for supporting protective but removable enclosure-canvas, or the like.